EMI challenge to Ethernet in the car

Ethernet can now be added to the list of automotive networks, such as CAN, LIN, FlexRay and MOST. But why is it needed and for what applications?

The reason is simple and is why Ethernet totally dominates office networking and is now the choice for both factory and the home. Simplicity and field-proven open standardization have significantly lowered the Cost of Ownership in every application Ethernet has entered. Volumes of scale in the office and consumer market supported by a magnitude of Ethernet vendors have driven pricing levels far lower than any ‘custom’ designed protocol.

Initial applications include On-Board-Diagnostics (OBD), rapidly reducing software download times. There now seems to be a general consensus that OBD will move to an IP based interface ie. a physical layer of Ethernet rather than the traditional slower CAN. Moving forward ‘real time’ Ethernet AVB (Audio-Video Bridging) can also offer high performance infotainment network solutions, but here the challenge is not just purely technical. OBD applications have the benefit of being operational when the car is in the service garage ie. Not on the move. When the car is running more stringent EMI requirements are demanded by the car manufacturers. Ethernet was never designed specifically for such applications. So can it rise to the challenge?